Psychiatric patients with Vietnam combat experience have often been described as violent, and it has been hypothesized that their violence may be due either to Vietnam combat experiences or longstanding psychopathic tendencies, including criminality before entering the service. Criminal and military history of Vietnam era veterans diagnosed schizophrenic by DSM-III criteria were examined in relation to inpatient measures of assault. Seventy subjects were examined, of which 27 were in Vietnam and 19 of these 27 in combat. By using multiple regression techniques, it was determined that certain violent tendencies in schizophrenic Vietnam era veterans are better related to their war experiences than premorbid criminal behavior.